1. Field of the Invention
The present invention relates to a transmitting and receiving antenna for a portable telephone, and more particularly to an accommodating device which accommodates an antenna element inside the case of a portable radiotelephone so that the antenna element can be freely inserted into or withdrawn from the case.
2. Prior Art
Telephones are instruments used for two-way communication, and portable telephones are no exception to this rule. Telephones used as instruments for such two-way communication have a substantial problem in that it is impossible to predict when a call signal will be received from a calling party. Accordingly, in the conventional portable telephones, as shown in FIG. 5(a), an antenna element 1 projects outside of the case 2, thus insuring that a call signal can always be received. Incidentally, the portable telephone case 2 has the shape of a transmitter-receiver used in ordinary telephones.
Since the antenna element 1 constantly projects outside of the case 2 in conventional antennas as described above, the antenna element 1 is a nuisance when the telephone is not in use. Accordingly, it is desirable for the antenna element to be retracted inside the case 2 when the telephone is not in use.
FIG. 5(b) illustrates a telephone designed so that the antenna element 1 is simply accommodated inside the case 2 so that it can be freely pushed into or withdrawn from the case in response the above-mentioned demand. In this construction, however, the transmission/reception sensitivity of the antenna element 1 drops remarkably when the antenna element 1 is accommodated inside the case 2. As a result, the above-mentioned intrinsic function of the telephone, i.e., "the ability to receive any call signals at any time," is reduced significantly.